I frequently noticed that people seem to be having significant problems with fitting the big ships through the mailslot and into a station. Hence I am going to share a neat feature I have been using for a long time to safely get several different big ships into a station. I tested this with the Anaconda, the Type 9 Heavy, and the Beluga. Due to the vastly different cockpit placement on these vessels I can, with quite an amount of confidence, claim that this should work for other big vessels as well. Using this approach takes a fair bit of practice though, but as you will notice from the pictures below, I managed to get a Beluga into the docking bay without having to bother with lowering the landing gear first - meaning there is a fair bit of clearance left.

That being said, now what is the OLS I am referring to? Much like the system used on aircraft carriers, this OLS consists of several sets of lights which guide a pilot through their approach on landing.
To be precise there are four sets of lights as indicated on the picture below.
Outer Port Lights (red) on the outer parts of the grille
Outer Starboard Lights (green) on the outer parts of the grille
Outer Center Lights (red) just above and below the mailslot
Inner Central Lights (three red lights in a line on the structure protruding into the docking bay on the opposite side of the mailslot)

As you can see above, the key is, to keep the Inner Central Lights centered between all sets of outer lights - both horizontally and vertically. Having the dot widget in the center of your screen toggled on does make this approach substantially easier since it adds another point of reference for alignment.

Picture 1

Notice: The yellow dot widget in the center of the screen is turned on!

Picture 2

If you start your alignment far enough out from the grille you will have little trouble getting it right since you have plenty of room to maneuver.

Picture 3

Keep the widget over the structure on the far end of the docking bay.

Picture 4

It may feel as if you were approaching too high, but that is not the case as you will realize upon getting closer to the mailslot

Picture 5

Compensating the station's rotation is easy enough and even like this you have plenty of quite literal wiggle room in the mailslot.

Picture 6

As you can see you are actually low enough to pass through the mailslot - even without deploying the Beluga's landing gear.

Picture 7

And we are through the mailslot. Now you just need to land your ship on your designated pad. Don't forget deploying your landing gear ;-)

- Green goes to the right (Starboard), Red goes to the left (Port) when passing the slot - although technically it is not required, but all NPCs fly that way
- Green side of the slot is where you enter or exit (small/medium Ships but also a large Ship like an Orca or the Anaconda)
- Red side is where oncoming traffic will be (it's Green for them on the other Side of the slot respectively)

- if a large NPC Ship (T9, T10, Beluga) is inbound/outbound and maneuvering to pass the slot, you have to yield for it (unless you know for sure you can still fit)... because the NPC won't

I disagree - it is not a bug, the ship doesn't have a "magnetic effect" or any of that nonsense - it is purely a result of the slope of the top surface of the anaconda being "downwards" from the bridge view. If one ignores where the nose is pointing and instead uses the guide-lines from the secondary weapon reticules as your centre-line-of-travel then you will never scrape / rise up as you enter (or leave).

- Green goes to the right (Starboard), Red goes to the left (Port) when passing the slot - although technically it is not required, but all NPCs fly that way
- Green side of the slot is where you enter or exit (small/medium Ships but also a large Ship like an Orca or the Anaconda)
- Red side is where oncoming traffic will be (it's Green for them on the other Side of the slot respectively)

- if a large NPC Ship (T9, T10, Beluga) is inbound/outbound and maneuvering to pass the slot, you have to yield for it (unless you know for sure you can still fit)... because the NPC won't

I know about port and starboard - I just happened to be upside down when making those pictures. If you look at the list, you will notice that both are written down correctly there. As for traffic, you are correct, but during this approach you can always move over to the side by using lateral thrusters if you have to. Otherwise you in your big ship have right of way ;-)

I disagree - it is not a bug, the ship doesn't have a "magnetic effect" or any of that nonsense - it is purely a result of the slope of the top surface of the anaconda being "downwards" from the bridge view. If one ignores where the nose is pointing and instead uses the guide-lines from the secondary weapon reticules as your centre-line-of-travel then you will never scrape / rise up as you enter (or leave).

Hmmm...did a bit more research on this...some people are saying it's "self-correction" which seems odd as it does not appear to happen in any other (big) ships (though that would explain why it only happens on exit and not entry), others are saying it's rotational-correction turning off too soon (which I doubt because the ship is still parallel with the slot when this happens). Rather than speculate I'm going to do my own testing and come to my own conclusion.

Hmmm...did a bit more research on this...some people are saying it's "self-correction" which seems odd as it does not appear to happen in any other (big) ships (though that would explain why it only happens on exit and not entry), others are saying it's rotational-correction turning off too soon (which I doubt because the ship is still parallel with the slot when this happens). Rather than speculate I'm going to do my own testing and come to my own conclusion.

I am not sure, this was actually intended to work as OLS, it just happens to. But since the signal mast inside the docking bay is surrounded by a circular pattern on the ground, it is fairly easy to maintain alignment even when the lights are in the off-part of their sequence.

Hmmm...did a bit more research on this...some people are saying it's "self-correction" which seems odd as it does not appear to happen in any other (big) ships (though that would explain why it only happens on exit and not entry), others are saying it's rotational-correction turning off too soon (which I doubt because the ship is still parallel with the slot when this happens). Rather than speculate I'm going to do my own testing and come to my own conclusion.

Yes I know lots of people think there is a magic attractor in an anaconda - just do it using the reticules, ignore where the nose is pointing, and you will see that you don't raise up. You can even use a docking computer to check if you don't believe me. People just can't get their head round the fact that the nose points down - even though they see it all the time in supercruise with the fence-post movement and when using weapons.

I'm not near my annies at the moment but here is an old screenshot showing the aligning using the HUD secondary weapon reticules' centre-lines:

You will see that the nose seems to point below the slot but a line between the two HUD reticule marks is just below the top of the slot. This was on exiting, the same is true on entry.

Great guide !
-Anaconda,stick cockpit in to ceiling when going through slot and all is good
-green,red,left,right. It doesn't matter which side the lights are as long as you use the GREEN side when going through. I am British and have green on the left
-Slot alignment,OP's method is great but I use the mouse dot in the center of my screen(I know most don't have it enabled)

I believe SJA said she altered the NPC behaviour to "stick to the green" after players adopted it. I have only been playing for 3 years so I don't remember them not doing this.

Similarly, I don't think I have ever seen a NPC go through the slot "upside down" - I'm sure I would have noticed - I see them rotate to be "the right way up" (green to right) when leaving and they always seem to be the right way up when entering in front of me.

Great guide !
-Anaconda,stick cockpit in to ceiling when going through slot and all is good
-green,red,left,right. It doesn't matter which side the lights are as long as you use the GREEN side when going through. I am British and have green on the left
-Slot alignment,OP's method is great but I use the mouse dot in the center of my screen(I know most don't have it enabled)

the number counts, not the side.
green to right means, numbers start at 1 right below the slot
with the green to the left its the 24,
so depending on the numbers i use both sides and my pad is always more the less below me